A surface profile measuring instrument that measures a profile of a surface of a workpiece with a contact probe attached to a coordinates measuring machine has been known. The instrument continuously measures the surface profile of a workpiece by scanning and profiling the surface of the workpiece with a tip end of a stylus. A conventional surface profile measuring instrument has a contact probe having a contact portion for contacting the surface of the workpiece, a drive mechanism for moving the contact probe in X, Y, and Z directions, and a controller that controls the movement of the contact portion of the contact probe through the drive mechanism.
In measuring, the above contact probe of the surface profile measuring instrument may deform or can be damaged under a pressure. So, the capability of the instrument is degraded and may, because of its deformity, damage a workspace such as marring the surface of a lens.
It is desired to provide a non-contact surface profile measuring apparatus which can overcome the above-described deficiencies.